The present invention relates to a thin film transistor liquid crystal display (TFT-LCD) array substrate and a method of manufacturing the same.
Thin film transistor liquid crystal displays (TFT-LCDs) are dominating in the current flat panel display market because they have small volume, low power consumption, non-radiation and so on. For a TFT-LCD, an array substrate and the process of manufacturing the same determine the product performance, yield and price thereof. In order to effectively decrease the price of TFT-LCDs and improve yield, the process of manufacturing a TFT-LCD array substrate is gradually simplified and has been developed from the initial seven mask (7-Mask) process to four mask (4-Mask) process based on the slit photolithography technology.
At present, a TFT-LCD array substrate is manufactured by forming a set of thin film patterns via a set of patterning processes, and each patterning process forms one layer of thin film pattern. The 4-Mask process technology currently used comprises a half-tone mask or a gray-tone mask process, through which patterns for an active layer, a data line, a source electrode, a drain electrode and a TFT channel region are formed in a lump. Because the pattern of a mask is converted to a thin film pattern in each patterning process and each layer of the thin film pattern need to be precisely stacked above another underlying layer of thin film pattern, there are the less the amount of the mask used and the shorter the manufacturing time, the higher productivity and the lower the manufacturing cost are incurred during the process for manufacturing the TFT-LCD array substrate.